Book I am reading.

I have been reading a book, The World's Last Mysteries.  It tells of various ancient civilizations and what may have caused their rise and fall.  Atlantis may be only fiction but others like the ruins of Stonehenge, Easter Island, Aztec and Mayan ruins are amazing in that primitive people were able to find ways to quarry and move enormous stones to distant places without even the benefit of the wheel.  Archaeologists believe that large slave labor, was necessary although they did make use of levers and ropes, rocking motions, and wood scaffolding to aid them.  I believe also that it was a way to control people through concocting a religion that kept people busy erecting these monuments (and therefore less likely to revolt) so the heads of governments, often shamans, could keep them under submission.  The people of the Indus Valley (from near eastern Iran, Pakistan, and part of northern India) may not have been as influenced by religion but a powerful central government controlled the building of homes of monotonous similarity with almost no decoration.  People probably did not have much freedom or ownership of property except for personal things.  The central government was able to plan cities based on a grid street system with courtyards, covered sewer systems, canals from the river, etc.  But at some point, perhaps because of political instability at the top or a possibly revolt, it all came to a halt.  Also flooding might have been a factor.